Drill



Feb. 11, 1930.

H. c. NORL EY DRILL Filed July 26, 1935 Patented Feb. 11, 1936 DRILL Harry Charles Norley, Peterboro, Ontario, Canada, assignor to Canadian Atlas Steels Limited, Welland, Ontario, Canada, a corporation of Canada Application July 28, 1935, Serial No. 33,350

11 Claims.

My invention relates to improvements in drills. particularly intended for use in rock drilling and of the detachable bit type, and the object of my invention is to devise a drill of the type described and claimed in my United States Patent No. 1,974,540, issued September 25, 1934, but which will present an improved construction thereo'ver so that my resultant drill will be more rugged and durable and can be more readily and cheaply fabricated.

With the above and other objects in view which will hereinafter appear as the specification proceeds, my invention consists, in its preferred embodiment, of the construction all as hereinafter more particularly described and illustrated in the accompanying drawing in which:-

Fig. 1 represents a side view of my drill showing the shank and bit detached from each other.

Fig. 2 is a similar view to Fig. 1 only showing the bit attached to the shank, the former being illustrated in section.

Fig. 3 is a similar view to Fig. 2 only viewed at right angles thereto.

Fig. 4 is a side view of the shank, showing it in the initial position it assumes in connecting the bit thereto, the latter being shown in section.

Fig. 5 is a plan view of my bit, and

Fig. 6 is an inverted planview of my shank.

Like characters indicate corresponding parts in the different views.

My shank i preferably comprises a bit engaging end or tongue 2 of circular cross-section adapted to be received into a correspondingly shaped socket 3 in my bit 4 provided with the cutters 5. The upper portion of the tongue 2 and the upper portion of the wall of the socket 3 is of slightly larger diameter than the lower portion of the tongue and the lower portion of the socket thus providing a shouldered tongue receivable into a correspondingly shouldered socket in the bit.

On the side wall of the tongue 2 at the junction of the upper'and lower portions I provide a projection 6 and a protuberance l diametrically positioned with respect to each other and each consisting of a laterally extending rib protruding outwardly from the side wall of the tongue. The projection 6 is preferably more prominent than the protuberance 7. Between the projection 6 and the protuberance I I provide on the upper portion of the side wall of the tongue two diametrically opposed laterally extending lugs 8 which taper from top to bottom and are adapted to be received into corresponding tapered notches 9 extending downwardly from the lip of the wall 80 9f the bit 4 surrounding the s'o'cket 3, said lugs and notches constituting the driving connection between the bit and shank for ensuring that the bit is rotated as the shank is rotated. I

When the bit is applied to the shank the pro- 5 jectiont and the protuberance I are received into a circumferential groove ll formed in the wall of the socket 3, thus constituting the means for preventing the bit being longitudinally displaced from the shank particularly when the 10 drill is being withdrawn from the hole bored.

In applying the bit to the shank it is disposed so that its longitudinal axis is at an angle to the longitudinal axis of the shank and the tongue 2 is inserted into the socket 3, the protuberance 1 1'5 being hooked or partially inserted into the groove H (see Fig. 4). Then by swinging the bit relativelyto the shank so that their longitudinal axes become coincident, the projection 6 is forced down into the groove II in which position the tongue 2 20 is a driving fit in the socket 3, with the projection 6 and protuberance I fully received in the groove II.

Owing to the connection between bit and shank being ofv necessity a very tight one, the bit is 25 applied to the shank by tapping or hammering it on. To remo've'the bit from the shank the reverse procedure is adapted to that indicated above, it being necessary to first swing the bit so that the longitudinal axis is disposed at an angle 30 to that of the shank before it can be removed therefrom.

Although I have described the tongue as being on the shank and the socket in the bit, the construction is such that these parts could be re- 3 versed.

Furthermore, instead of providing a shouldered tongue 2 on the shank and a correspondingly shouldered recess or socket in the bit, the bit engaging end of the shank could be tapered to- 40 wards its extremity in which case the socket wall of the bit would be correspondingly tapered to receive it.

A drill constructed according to my invention is more readily fabricated than that described in 45 my previous patent above referred to and the circular socket and tongue being easier to form. Furthermore, the lug and notch driving connection between bit and shank is a very positive one and can be readily fabricated.

What I claim as my invention is:

1. In a drill, the combination with a shank portion and a detachable bit portion, of a nonrotative connection between the two portions comprising a lateral lug on one portion received 55 into a notch in the other portion, and coacting means on the respective portions adapted to interlock with each other, said portions being initially applied to each other-so that the longitudinal axis of one portion is at an angle to the longitudinal axis 01' the other portion where in the lug and notch and the interlocking means partially engage and finally such portions being so disposed that their longitudinal axes are coincident. wherein the lug and notch and the locking means fully engage to constitute respectiveiy a driving connection between the portions and means for preventing longitudinal displacement of one portion from the other.

2. In a drill as claimed in claim 1, diametrically opposed ribs on one portion receivable into a groove in the other portion constituting the interlocking means.

3. A drill comprising, in combination, a shank portion and a detachable bit portion, a tongue on one portion receivable into a socket in the other portion, laterally extending lugs on the tongue receivable into notches in the other portion adapted to constitute a non-rotative connection therebetween, and ribs on the tongue adapted to be received into a groove in the wall of the socket constituting means for preventing longitudinal displacement of one portion from the other, said portions being initially applied to each other so that their longitudinal axes are at an angle to each other wherein the lugs partially engage the notches and one of the ribs partially engages the groove in the socket wall, and said portions being finally disposed so that their longitudinal axes are coincident wherein the lugs fully engage the notches and the ribs fully engage the groove in the socket wall.

4. A drill as claimed in claim 3 wherein the tongue and socket are correspondingly shouldered and constitute a driving fit when fully applied to each other.

5. A drill as claimed in claim 3 wherein the ribs are arranged on the tongue diametrically opposite each other and the lugs are also diametrically opposite each other with each lug positioned between adjacent ends of the ribs.

6. A drill comprising, in combination, a detachable bit portion having a central socket with a circumferential groove in the socket wall and notches in the top thereof, a shank portion having a bit engaging tongue at one end insertable into the socket oi the bit portion, laterally extending lugs formed on the tongue insertable into the notches in the top of the socket wall of the bit portion, and ribs formed on the tongue insertable into the circumferential groove in the socket wall of the bit portion, said portions being initially applied to each other so that their longitudinal axes are at an angle wherein the lugs partially engage the notches and one of the ribs partially engages the circumferential groove, and being finally applied to each other with their longitudinal axes coincident wherein the lugs fully engage the notches and the ribs iully en gage the circumferential groove.

7. A drill as claimed in claim 6 wherein the tongue and socket are correspondingly shouldered andconstitute a driving fit when fully applied to each other.

8. A drill as claimed in claim 6 wherein the ribs are arranged on the tongue diametrically opposite each other, and the lugs are also diametrically opposite each other with each lug positioned between adjacent ends of the ribs.

9. In a drill, in combination, a detachable bit portion having a central socket with a. circum- Ierential groove in the socket wall, and a shank portion including a tongue at one end insertable into the socket in the bit portion, said tongue having lateral ribs insertable into the circumferential groove in the socket of the bit portion, said portions being initially applied to each other so that their longitudinal axes are at an angle wherein one of the ribs on the tongue partially engages the circumferential groove in the socket of the bit portion, and being finally disposed so that their longitudinal axes are coincident with each other wherein the ribs on the tongue fully engage the circumferential groove in the socket of the bit portion, and coacting means partly disposed on the shank and partly on the bit portion for establishing a non-rotative connection therebetween.

10. A drill as claimed in claim 9 wherein the tongue and socket are correspondingly shouldered and constitute a driving fit when fully applied to each other.

11. A drill as claimed in claim 9 wherein the ribs are arranged on the tongue diametrically opposite each other.

HARRY CHARLES NORLEY. 

